S Y N T H E S I S OF N 2, N 2 ' - A L K Y L E N E D I A S P A R T I M I D E S

T . V. S h e r e m e t e v a , G. S. S h a r i f o v , E . F . Z a z y k i n a , a n d T . A. K a l i n i n a

UDC 542.91 +547.398 +547.466.63

The bifunctionali ty of unsa tura ted imides is dis t inct ly mani fes ted in the i r reac t ion with al iphatic amines [1, 2]. The reac t ion , depending on the pH of the reac t ion mix ture , may p roceed in different d i r ec - t ions. In an absolute ly dry medium, i . e . , when the amide is only in an amino fo rm and the s y s t e m con- ta ins no OH- and RNH~" ions, only addition of the amine at the double bond occurs with the format ion of the cor responding imides of a spa r t i c acid; even upon the introduction of a l a rge excess of amine into the reac t ion mixture , the imide r ings a r e p r e s e r v e d . In the p r e sence of moi s tu re at pH 10-11, there is an amino lys i s of the imide r ings , which is accompanied by hydro lys i s .

It was of in te res t to extend these reac t ions to d iamines s ince, depending on the exper imenta l condi- t ions, one can expect the fo rmat ion of var ious polyfunctional m o n o m e r s , which a re s tar t ing substances for the synthes is of h igh=molecular compounds. The p resen t a r t i c l e is concerned with the study of the reaeHon of N-subs t i tu ted imides of male ic and e i t raconic acids with the following diamines: e thylenediamine (EDA), p iperaz ine , and hexamethylenediamine (HMDA). The expe r imen t s were c a r r i e d out in the absence of m o i s - ture in abs. alcohol or toluene solution. As would be expected, this led to the format ion of N2,N2'-alkylene - d i a spa r t imides (Schemes 1 and 2 and Table 1). The s t ruc tu re of the di imides was proved by chemica l and physical methods. The e lementa l composi t ions co r re sponded to those calculated: the products fai led to undergo hydrogenat ion over a Pd ca ta lys t , thus indicating that they contain no double bonds; the amino groups can be t i t r a ted with hydrochlor ic or pe rch lo r i c acid. T r e a t m e n t with conc. HC1 gives hydrochlor ides which in the reac t ion with ni t rous acid a r e t r a n s f o r m e d to N-n i t roso der iva t ives ; the action of ammonia or

I00

50

100

v 50

.~ 1oo

50 .=.

F~ fO~

50

r i i r

3Z00 1800 I600 1~00 lZOO 1000 v, c m -

/O0

100 r I I

50 + . ~

:~ lot

~ 6c

1os

3200 I800 1600 l~O0 1200 1000 ~, c m -~

Fig. 1 Fig. 2 Fig. 1. IR s p e c t r a of diimides: 1) product I; 2) product II; 3) product III; 4) product IV.

Fig . 2. IR s pec t r a of diimides: 1) product V'; 2) product V"; 3) product VI; 4) product VII

Inst i tute of High Molecular Compounds, Academy of Sciences, of the USSR. Izves t iya Akademii Nauk SSSR, Seriya Khimieheskaya , No, 5, pp. 1136-1144, 1970. mit ted November 1, 1968.

Trans la t ed f rom Original a r t i c le sub-

1072

/ N H--R ~ ,',,' Hky.._.~

+%>0 I t R ~ + r

] (l) r = CH+, r ' : (C~D+ HCI HCI

(la) R=CHa, R'=(CH})~ i

(Ila) R= CH a, R!= (CH2)~ i~+ (IVa) R = C~Hs, R l = (CH~)~

z I (I1) R : CH a, R'= (CH~ +HCI (Ill) R ~ C~Hs, RI= (C~j~

"~ (IV) R = C6H5, r ~= (CI-i~j~

SH ~n NH SH I I, I,, ! R R' R R

(IB) R = CHa, R~= (CHe)2, RII:CH a (IIn) R = C}'Ia, R I= (CH=)~, R~ H

N=O N=O I , I

/ _ _ ~ N - - r =NN/__, ~

o%,N)=o

(16) R = CHa, Rt= (CH2) ~ (II6) R = CHa, RI: (CH2) 8

Scheme I

R t R ~ R t

0<75=0+ x , ~ (vm)

R1 HCI/---~HCI -t Rt ~'/'-'~N R ~ +N~_/N R

I I + ~ (V%(V t') R =CHa,R+=H + R R R

~i (VI) R=C~H~, R+= H (V+a), (Vt~a) R = CH 3

R+: H (VII) R =C6H 5,Rt=CHa

HN NH 2 H~N NH 1 I R R

(V%) R=CHa, Rt=H (Vls) R:C~H~,R +=H

Scheme 2

a m i n e s y ie lds the c o r r e s p o n d i n g t e t r a a m i d e s as a r e s u l t of a m i n o l y s i s of imide g roups ; the II~* s p e c t r a show a b s o r p t i o n bands c h a r a c t e r i s t i c of CO g r o u p s in the 5 - m e m b e r e d imide r ing (Fig. t ) .

I t is of i n t e r e s t to note tha t N2 ,N2 ' :N2 ,N2 ' -d i e thy leneb i s -Nl -me thy la spa r t imide f o r m e d in the r eac t i on of p i p e r a z i n e with m e t h y l m a t e i m i d e was obta ined in two i s o m e r i c f o r m s d i f fe r ing by c h e m i c a l and phys ica l p r o p e r t i e s : mp of V ' , 176-177% re a d i l y soluble in a lcohol and wate r ; mp of V", 240-241 ~ spa r ing ly so lu - ble in a lcohol and wa te r . The m o l e c u l a r weights d e t e r m i n e d c r y o s c o p i c a l l y in g lac ia l CHaCGOH a r e p r a c - t i ca l ly the s a m e fo r both p roduc t s and c o r r e s p o n d to that ca l cu la t ed within the r ange of expe r imen t a l e r r o r : mol . wL of V ' , 281; mol . wt. of V", 286. The m o l e c u l a r weight d e t e r m i n e d in wa te r fo r t h e ' l o w - m e l t i n g i s o m e r is 316 (ca lcu la ted tool. wt. is 308). High mel t ing V" i s o m e r f o r m s both a m o n o h y d r o c h l o r i d e (the amoun t s of ch lo r ine in the h y d r o c h l o r i d e s , d e t e r m i n e d a r g e n t o m e t r i c a l l y , c o r r e s p o n d e d to that ca lcula ted) . In a c c o r d with this , both amino g roups can be t i t r a t ed in the h i g h - m e l t i n g i s o m e r and only one amino g roup

* IR s p e c t r a were r e c o r d e d on a DS-301 i n s t rumen t .

1073

T A B L E i. N 2 , N 2 ' - A l k y l e n e d i a s p a r t h i m t d e s S y n t h e s i z e d

Initial reagents No. of

Compound imide am[de

III

IV

V '

V"

VI

VII

N-Methylmaleimide

The same

N -Phenylmaleimide

The same

N - Methylmaleimide

The same

N -Phenylmaleimide

N-Phenylcitraconimide

Ethylenediamine

Hexamethylenediamine

Ethylenediamine

Hexamethylenediamine

Piperazine

The same

. N

Temperature, ~

146-148

115

210-211

151-151.5

178-179

240-241

239-240

188-190

Solubility

Glacial CHsCOOH, water, and alcohol

Glacial CHsCOOH, di- methylformamide, water, alcohol, ben- zene, toluene, and chloroform

Hot dimethylformamide, hot benzyl alcohol, and glacial CHzCOOH

Glaeial CH3COOH, di- methylformamide, chloroform, dioxide, hot toluene, and hot a c e t o n e

Glacial CHaCOOH, water, and alcohol

Glacial CHsCOOH, and hot water

Glacial CHaCOOH, and hot dimethylformamide

Glacial CH~COOH, hot water and alcohol

in the l o w - m e l t i n g i s o m e r . The IR s p e c t r a (F ig . 2) and n u c l e a r m a g n e t i c r e s o n a n c e s p e c t r a (F ig . 3)* of

both i s o m e r s w e r e i d e n t i c a l .

Al l the d a t a g iven s t r o n g l y s u p p o r t s t e r e o i s o m e r i s m , r a t h e r than s t r u c t u r a l i s o m e r i s m . We have c o n s i d e r e d the u se of NMR in the a n a l y s i s of the s t r u c t u r e of the i s o m e r s , but the m e t h y l g r o u p s , the s i g - na l s of which a r e the n a r r o w e s t and t h e r e f o r e the m o s t s u i t a b l e fo r m e a s u r i n g the d i f f e r e n c e in the c h e m - i c a l sh i f t s of v a r i o u s s t e r e o i s o m e r s , a r e v e r y f a r r e m o v e d f r o m the p i p e r a z i n e r i ng . T h e i r e l e c t r o n i c and g e o m e t r i c e n v i r o n m e n t is p r a c t i c a l l y the s a m e tn bo th i s o m e r s . I t is p o s s i b l e tha t on a m o r e s e n s i t i v e i n s t r u m e n t the d i f f e r e n c e in the s i g n a l s of the m e t h y l g r o u p s can be d e t e c t e d .

T h e o r e t i c a l l y , the e x i s t e n c e of a g r e a t n u m b e r of i s o m e r s is p o s s i b l e . The p y r a z i n e r i ng can e x i s t in two f o r m s : b o a t f o r m and cha in f o r m . Two s t e r e o i s o m e r s wi th a x i a l and e q u a t o r i a l c o n f i g u r a t i o n s of the s u b s t i t u e n t s a t the n i t r o g e n a t o m m a y c o r r e s p o n d to each of the two f o r m s . M o r e o v e r , the m o l e c u l e c o n - t a i n s two a s y m m e t r i c c a r b o n a t o m s , c o n s e q u e n t l y , t h e r e a r e p o s s i b l e levo , d e x t r o , and m e s o f o r m s , and r a c e m i c m i x t u r e s . The s o l u t i o n of the p r o b l e m of the s t r u c t u r e of the i s o m e r s r e q u i r e s s p e c i a l i n -

v e s t i g a t i o n .

I t shou ld be a l s o no ted tha t the r e a c t i o n of d i a m i n e s wi th u n s a t u r a t e d [ m i d e s r e v e a l e d m a r k e d d i f - f e r e n c e s in the r e a c t i v t t i e s both of the double bonds and of the i m i d e r i n g s , a t t r i b u t a b l e to the c h a r a c t e r of the s u b s t i t u e n t s a t the double bond and at the i m i d e n i t r o g e n a tom. F o r e x a m p l e , N 2 , N 2 ' - e t h y l e n e b i s - N 1- p h e n y l a s p a r t i m i d e was s o m e t i m e s o b t a i n e d in a d m i x t u r e wi th 3 - o x o - 2 - p [ p e r a z i n e a c e t a n i l i d e (IX), which was f o r m e d a s a r e s u l t of s i m u l t a n e o u s o c c u r r e n c e of both r e a c t i o n s : the a d d i t i o n of one a m i n o g r o u p to the double bond of the i m i d e and a m i n o l y s i s of the s a m e i m i d e r i n g by the s e c o n d a m i n o g roup of e t h y l e n e d [ - a m i n e . Thus , the i m i d e r i n g was r e a r r a n g e d t o a p i p e r a z i n e r i n g , con t a in ing the a m i d e g r o u p i n g in the

s i de c h a i n

o II NH

/ \

[] NH o (Ix)

* NMR s p e c t r a w e r e r e c o r d e d on i n s t r u m e n t J N M - 3 .

1074

1 Y

Fig. 3. NMR spectra: 1) of product V'; 2) of product V".

~ o 3200 /800 1600 I~00 1200 IOgO u, cm'1

Fig. 4. IR spectrum of product IX.

The simultaneous occur rence of both p rocesses in these cases can be at- tr ibuted to the inadequate dehydration of the react ion medium and the weakening of the imide link under the influence of the e t ec t ron-accep to r phenyl nucleus at

the ni trogen atom. The influence of the phenyl group on the react ivi ty of the ira[de link is most distinctly manifested in N-phenylci t raconimide, the double bond of which is screened by the bulky methyl group. In this case , in react ion with EDA no addition at the double bond occur red at all, and the product of the aminolysis of two phenylci t raconimide molecules by one EDA molecule was isolated

0 0 o

\ / \ / - , . / \/\ H~N(CH~)~NH~-> I] \NH(CH2)~NH/ ]I

o tJ H o (• o

i. e . , N ,N"-e thy lenebis -N ' -phenylc i t raconamide (X) was formed.

The interaction of phenylci t raconimide with piperazine gave two s t ruc tura l i somers : the diethylene- b is (2-methyl -Nl-phenylaspar t imide) (VII) as a resul t of the addition of piperazine at the double bonds of the imide rings and N,N":N,N"-die thylenebis -N' -phenylc i t raconamide (VIII) as a result of aminolysis of imide rings by piperazine with the preserva t ion of the double bonds.

E X P E R I M E N T A L

Male[re[de and c i t raconimide were r ec rys ta l l i zed f rom alcohol o r toluene and dried in a vacuum d r y e r to constant weight. N-Methylmaleimide (MMI), mp 94-95 ~ (according to l i te ra ture data, 90-92~ N-phenyl- male[re[de (PMI), mp 89-99 ~ (according to l i t e ra ture data 90-91~ N-phenylci t raconimide (PCI), rap 99-100 ~ (according to l i t e ra ture data 98-99~ Ethylenediamine (EDA) and hexamethylenediamine (HMDA) were f i rs t distilled over alkali and then over metall ic sodium. EDA, bp 116-117~ KMDA, bp 195-196 ~ Piperazine was dried for a long t ime over alkali in a des icca tor to a constant melting point of 104 ~

N~,N~'-Ethylenebis-Nl-methylaspart imide (I). To a solution of 5.5 g of MMI in abs. alcohol was added 1.3 g of EDA in abs. alcohol at room tempera ture at a rate of 50-60 drops a minute with s t i r r ing. After the completion of the addition of EDA solution, s t i r r ing was continued for another hour and the mixture allowed to stand for 16 h. The result ing precipitate was f i l tered off and rec rys ta l l i zed f rom alcohol. The yield of I was 2.8 g (40%), mp146-148 ~ The elemental composit ion cor responds to the product formed in the addi- tion of two MMI molecules to one EDA molecule. Found: C 51.19; H 6.52; N 20.04%. CnHIsOtN 4. Calcu- lated: C 51.06; H 6.38; N 19.89%. Equivalent, de termined by t i t rat ing with 0.1 HC1, was 289, i . e . , one amino group was t i trated. The IR spec t rum (see Fig. 1) of the product showed absorption bands in the region 1690, 1760 and 3300, 3400 cm -1. The s t ruc tu res of the compounds were supported by prepar ing der iva- t ives. The proper t i es of the resul t ing diimides a re given in Table i .

Dihydrochloride In. This was obtained by adding a large excess of 11 N HC1 to the product I. The excess of HC1 and water was removed by drying in a des icca tor over alkali, mp 230 ~ (from aqueous alcohol). Found: C1 20.00%. C12H18OtN2.2HC1. Calculated: C1 19.80%.

Dini t roso-Der ivat ive lb. To a concentrated solution of Ia was added a calculated amount of NaNQ in water. The result ing oil was dried and rec rys ta l l i zed f rom an a l c o h o l - w a t e r mixture. Found: N 24.70%. Ci2H~O ~. Calculated: N 24.72%.

Tet raamide Ic. A concentra ted aqueous solution of CH3NH 2 was added to product I, and the mixture was re f r ige ra ted for 3 days. The residue was f i l tered off and rec rys ta l l i zed f rom alcohol, mp 205 ~

1075

0 3200 ~ m 1 i '~ I o , 8,oo , , , , , , , ,

3280 1800 1600 1~0 1200 1800 v, cm -I

Fig. 5. IR spec t rum of product X. Fig. 6. IR spec t rum of product VIII.

Found: N24.78%. C14H2804N ~. Calculated: N24.41%. The charac te r i s t i c absorption bands in the IR s p e c - t rum are at 1555, 1640, and 3300 cm -1.

N2,N2'-Hexamethylenebis-Nl-methylaspart imide (II). The reaction was ca r r i edou t in abs. toluene s imi la r ly to the method descr ibed above. A mixture of 6.07 g of MMI and 3.00 g of HMDA gave 6.4 g (71%) of a product, mp 115 ~ (from a mixture of toluene and alcohol). The equivalent determined by t i tration with 0.1 N HC1 was 169, i . e . , both amino groups underwent titration. Found: C 56.80; H 7.92; H 16.56v/o. CI~H26 �9 O4N 4. Calculated: C 57.10; H 7.96; N 16.42%. The IR spec t rum showed absorpt ionbands at 1700, 1770 and 3300, 3400 cm -i.

Dihydroehloride Ifa. Two grams of II gave 2.18 g (90%) of dihydrochloride, s imi lar ly to that des- cribed above, of mp 223-224 ~ (from aqueous alcohol). Found: C1 17.42%. C16I-I2~O4N4.2HC1. Calculated: CI 17.27%.

Dinitroso-Derivative lib. A mixture of 1 g of IIa and 0.2 g of NaNO2 gave 0.98 g (100~o) of ITb, mp 163-164 ~ (from water). Found: N 21.21%. CI6H240~N 6. Calculated: N 21.49%.

Tetraamide IIe. Aqueous ammonia was poured over 1 g of product If and the mixture refrigerated for 3 days. The resulting precipitate was filtered off and recrystallized from alcohol. Yield of ITc, 0.95 g (860/0); mp 198 ~ Found: N 22.600/0. CI6H3204N ~. Calculated: N 22.60%. Characteristic absorption bands in the IR spectrum are at 1560, 1650, and 3300 cm -i.

.N2,N2'-Ethylenebis-Ni-phenylaspartimide (III). The reaction was carried out similarly. A mixture of 17.3 g of PMI and 3.0 g EDA gave 19.0 g (93~ of a product, mp 210-211 ~ (from dimethylformamide). The IR spectrum showed absorption bands at 1700, 1770 and 3300, 3400 em-1. Found: C 65.16; H 5.72; N 13.60%. C22H2204N 4. Calculated: C 65.02; H 5.42; N 13.79%.

N2,N2'-Hexamethylenebis-Nl-phenylaspartimide (IV). A mixture of 6.9 g of I~MI and 2.3 g of HMDA gave 5.6 g (60%)of a product, mp 151-151.5 ~ (from toluene). The IR spectrum showed absorption bands at 1700, 1770 and 3300, 3400 cm -l. Found: C 68.19; H 6.51; N 11.84; O 13.82%. C26H3004N 4. Calculated: C 67.53; H 6.50; N 12.12; C) 13.85%. The equivalent, determined by titrating with HCIO 4, was 219, i .e. , both amino groups underwent titration.

Dihydrochloride IVa. This compound was prepared from 2 g of IV similarly to the previous product. Yield, 1.8 g (77~ mp 199-200 ~ (from aqueous alcohol). Found: Cl 13.40~ C26H3004N4"2HCl. Calculated: CI 13.28%.

N2,N2': N2,N2'-D[ethylenebis-N1-methylaspartimide V' and V". To a solution of 14 g of MMI in 200 ml of abs. alcohol was added 5.44 g of piperazine in 300 ml of abs. alcohol. The resulting precipitate was re- peatedly washed with hot alcohol. The insoluble part, V", amounted to 8.9 g (45%), mp 240-241 ~ (from water). Theequivalent,foundbytitrationwith0.1 NHClO4inglaeial acetic acid was equal to 153, i .e. , both amino groups underwent titration. The molecular weight determined eryoscopically in glacial CH3COOH was 286, calculated 308. Found: C 54.80; H 6.93; N 18.13%. CI4H2004N 2. Calculated: C 54.50; H 6.40; N 18.10~0. IR spectrum showed absorption bands at 2825, 2950, 3450 and 1690, 1760 em -I.

The product V' was isolated from the alcohol solution. Yield, 7.6 g (40%), mp 178-179 ~ (from alco- hol). Molecular weight determined eryoscopically in water was 316; when using the same method in glacial CH3COOH the molecular weight was 281. Found: C 55.11; H 6.95; N 17.95%. Ci4H2004N4. Calculated: C 54.50; H 6.40; N 18.10%. The equivalent, determined by titrating with HCIO 4 was equal to 280, [. e., one amino group underwent titration.

1076

Hydrochlor ide V'a. This was obtained f rom V' by the addition of a large excess of 11 N HC1 with sub- sequent recrys ta l l i za t ion from an a l c o h o l - w a t e r mixture, mp 189-190 ~ Found: C1 11.(f/0, corresponding to monohydrochlor ide CltH2004Nt'HC1. Calculated: C1 10.31%.

Hydrochlor ides of Product V", These were obtained s imilar ly; mp 210-212 ~ (from aqueous alcohol). Found: C1 10.90%, corresponding to C14H2004Nt'HC1. Calculated: C1 10.31%. The fi l trate gave a small amount of c rys t a l s , mp 323-324 ~ (from aqueous alcohol). Found: C1 18.60%, corresponding to dihydrochlo- ride V"a. CI4H20OtNt.2HC1. Calculated: C1 18.65%.

Tet raamide V"c. This was obtained f rom V" s imi la r ly as descr ibed above: mp 249-251 ~ (from aque- ous alcohol). Found: N 20.970/0. CltH26OtN 4. Calculated: N 21.06v/0. The equivalent, determined by t i t ra - tion with 0.1 N HC104 was 173; calculated, 171. Charac ter i s t ic absorption bands in IR spect rum are at 1560, 1640, 3000 and 3300 cm -l.

N2,N2':N2,N2'-Diethylenebis-Nl-phenylaspartimlde (VI). A mixture of 32.9 g of PMI and 8.16 g of piperazine gave 37 g (90%) of VI, mp 239-240 ~ (from HCON(CH3) 2. Found: C 66.14; H 5.80; N 12.91%. C24H24 -OtN 4. Calculated: C 66.66; H 5.51; N 12.9~ The equivalent determined by t i trat ing with HC104, was 238, i. e . , both amino groups underwent t i tration. The IR spec t rum showed absorption bands at 1700, 1770, and 2800 cm -I.

Tet raamide VIe. F r o m 2.30 g of VI was obtained 1.5 g (60~0) of te t raamide s imi la r ly to that descr ibed above, mp 224-225 ~ (fromHCON(CH3)2). Found: N 17.77%. C2tHa0OtN 6. Calculated: N 18.00~ The equi- valent, determined by t i t rat ion with 0.1 N HC10 t was 233, i . e . , both amino groups underwent t i tration. The charac te r i s t i c absorption bands in the IR spec t rum are at 1530, 1660, and 2800 cm -1.

Reaction of PMI with EDA in the Absence of Hermet ic i ty in the System in the P resence of Nonabsolute Solvents. To a solution of 6.92 g of PMI in alcohol we added 2.4 g of EDA in alcohol, and the mixture was a l lowed to stand at room tempera tu re for 2-3 days. The precipi tate was f i l tered off and washed with hot alcohol. The alcohol-soluble part of the product amounted to 0.52 g (6~ mp 210-211 ~ (from HCON(CH3)2); the elemental composit ion of this cor responds to the product obtained by adding two PMI molecules to one EDA molecule. The IR spec t rum showed absorption bands at 1700 and 1770 cm -1, charac te r i s t i c for C = O groups in a 5 -membered imide ring. Thus, the product was the diimide III.

Crys ta ls of mp 159-159.5 (from alcohol) were obtained from the alcohol solution. Yield, 3.46 g (44%}. Elemental composi t ion cor responds to the product obtained by adding equimolar amounts of PMI and EDA. Found: C 61.84; H 6.68; N 17.72%. Ct2H1502N 3. Calculated: C 61.80; H 6.43; N 18.00~ IR spec t rum (Fig. 4) showed the disappearance of absorption bands at 1700 and 1770 em -1 charac te r i s t i c for C = O in a 5 - m e m - bered imide ring and the appearance of an absorption band at 1660 cm -1 charac te r i s t i c for the C O - N H - group in the lac tam ring and the open chain. The product failed to undergo hydrogenation on a Pd catalyst , thus indicating the absence of a double bond. On this bas is the product was ascr ibed the s t ruc ture of 3-oxo- 2-piperazineaeetani l ide (IX). The equivalent, determined by t i trat ion with hydrochlor ic acid in water was 236, and with HC104 in glacial CH3COOH , 233; calculated, 233.

The hydroehlor ide of the product IX was obtained similar ly; mp 216-217 ~ (from aqueous alcohol). Found: C1 13.20%. C12H~502N3.HC1. Calculated: C1 13.17%.

The ni t roso derivative of product IX was also obtained by the conventional method, mp 191-192 ~ (from aqueous alcohol). Found: N 21.31%. C~2HItO3N 4. Calculated: N 21.33%.

Reaction of PCI with EDA. To a solution of 9.35 g of PCI in toluene we added 7 ml of an alcoholic solution of EDA (4 N, and the mixture was allowed to stand for 16 h. The precipitate was fi l tered off and dried; yield, 2.3 g (23%); mp 166-169 ~ (from alcohol). The IR spec t rum (Fig. 5) shows no absorption band charac te r i s t i c of C = O groups in the 5 -membered ring in the 1700 and 1770 cm -1 region; the spec t rum does show absorption bands charac te r i s t i c for amide groups and for double bonds (at 1540, 1630-1650~ 3250 era-l). The elemental composit ion cor responds tothe product obtained by adding two moles of PCI to one mole of EDA. Found: C 66.35; H 5.99; N 12.90c/0. C24H26OtN 4. Calculated: C 66.50; H 6.13; N 12.91%. The presence of double bonds was supported by hydrogenation over Pd/CaCO3. Two H 2 molecules were consumed to hy- drogenate one molecule of X. Thus, the product X is N,N"-e thylenebis -N ' -phenylc i t raconamide .

N2'N2':N2,N2'-Diethylenebis(2-methyl-Nt-phenylaspart imide) (VII). To a solution of 10.0 g of PCI in abs. toluene was added 2.3 g of piperazine in alcohol, and the mixture was allowed to stand at room tern-

1077

perature for 2-3 days. The precipitate in an amount of 10.8 g (88%) was washed with hot alcohol and the solution yielded 3.6 g {34%) of VII, mp 188-190 ~ Alcoholic solutions of VII showed an alkaline reaction. The equivalent, determined by t i trat ing with HC104 in CH3COOH was 235. Found: C 67.18; H 6.43; N 12.19%. The IR spec t rum showed absorption bands at 1700 and 1770 cm -1. In t e rms of these data, it was concluded that product VII is N2,N2':N2,N2'-diethylenebis(2-methyl-Nl-phenylaspartimide).

The alcohol- insoluble part of the product, 5.1 g (47%), was dissolved in HCON(CH3)2 and precipi - tated in ether. The IR spec t rum (Fig. 6) of the product of mp 235-235.5 ~ shows no absorption band cha rac - ter is t ic of C --O groups in the 5 -membered imide ring, it does show absorption bands charac te r i s t ic of C - O groups in amides (at 1530, 1620, 1650, 3200 cm-I) . The elemental composition corresponds to the product obtained by adding two PCI molecules to one piperazine molecule. Found: C 67.02; H 6.28; N 12.71%. C26H2804N 4. Calculate& C 67.82; H 6.09; N 12.19%. Two H 2 molecules were consumed for one molecule of VIII in the hydrogenation of Pd/CaCO 3. In t e rms of the given data it was concluded that VIII is N,N": N,N"-die thylenebis -N' -phenylc i t raconamide .

C O N C L U S I O N S

1. In the react ions of diamines with unsaturated cyclic imides, in the absence of moisture , the amino groups add at the double bond of the imides with the formation of the corresponding diimides.

2. N2,N2':N2,N2'-Diethylenebis-Nl-methylaspartimide is obtained in two s t e reo i somer ic forms.

3. Twenty-two compounds, which have not been descr ibed ear l ie r , have been synthesized and cha rac - ter ized.

1.

2.

L I T E R A T U R E C I T E D

T. V. Sheremeteva and V. V. Kudryavtsev, Izv. Akad. Nauk SSSR, Ser. Khim. , 189 (1966). T. V. Sheremeteva and K. A. Romashkova, Izv. Akad. Nauk SSSR, Ser. Khim. , 1474 (1966).

1078